FLARE FOR BATTLEFIELD ILLUMINATION

• US 20120087385A1
• Filed: 10/11/2011
• Published: 04/12/2012
• Est. Priority Date: 10/08/2010
• Status: Abandoned Application

• Current Assignee: Physical Sciences Incorporated
• Original Assignee: Physical Sciences Incorporated
• Inventors: Oakes, David B., Kessler, William J., Galbally-Kinney, Kristin L., Wainner, Richard T.
• Application Number:
  US13/270,796
• Publication Number:
  US 20120087385A1
• Time in Patent Office: Days
• US Class Current: 372/34
• CPC Class Codes: F41J 2/02 Active targets transmitting infrared radiation
• CPC Class Codes: F42B 4/26 Flares; Torches mines for practice or training containing flares or illuminating charges F42B8/28; projectiles of illuminating type F42B12/42
• CPC Class Codes: H01S 5/02212 Can-type, e.g. TO-CAN housings with emission along or parallel to symmetry axis
• CPC Class Codes: H01S 5/02469 Passive cooling, e.g. where heat is removed by the housing as a whole or by a heat pipe without any active cooling element like a TEC
• CPC Class Codes: H01S 5/4025 Array arrangements, e.g. constituted by discrete laser diodes or laser bar H01S5/42 takes precedence

Abstract

An infrared flare includes at least one diode laser configured to emit radiation in a near-infrared spectrum and an optical system configured to transform the radiation output from the at least one diode laser. Each of the at least one diode lasers are coupled to a laser mount. The infrared flare further includes a thermal management system configured to absorb waste heat generated by the at least one diode laser. The thermal management system is configured to maintain the laser mount at or below 60° C. during operation of the infrared flare.

Claims

1. An infrared flare comprising:

at least one diode laser configured to emit radiation in the near-infrared spectrum, each of the at least one diode lasers coupled to a laser mount;

an optical system configured to transform the radiation output from the at least one diode laser; and

a thermal management system configured to absorb waste heat generated by the at least one diode laser, wherein the thermal management system is configured to maintain the laser mount at or below 60°

C. during operation of the infrared flare.

2. The infrared flare of claim 1 wherein the at least one diode laser is configured to emit radiation having a wavelength ranging between 800 nm and 950 nm.

3. The infrared flare of claim 1 wherein the optical system includes at least one light shaping diffuser configured to transform an astigmatic output of the at least one diode laser into a flat top illumination profile.

4. The infrared flare of claim 3 wherein the at least one light shaping diffuser is further configured to remove laser speckle from the output of the at least one diode laser.

5. The infrared flare of claim 3 wherein the optical system includes a compound parabolic reflector that is configured to collect and concentrate the radiation emitted by the at least one diode laser.

6. The infrared flare of claim 5 wherein the compound parabolic reflector is further configured to improve the spatial uniformity of the radiation emitted by the at least one diode laser.

7. The infrared flare of claim 1 wherein the optical system receives the radiation emitted by the at least one laser diode, and wherein the optical system is further configured to provide at least a 1.26 steradian coverage of radiation with greater than 40% uniformity.

8. The infrared flare of claim 1 further comprising a battery configured to supply an operating current to the at least one diode laser.

9. The infrared flare of claim 8 wherein the battery includes a thermal battery.

10. The infrared flare of claim 1 wherein the at least one laser diode and the thermal management system are secured within a cylindrical housing, the cylindrical housing mechanically compatible with the M-278 flare package standard.

11. The infrared flare of claim 1 wherein the laser mount is coupled to a heat sink of the thermal management system, the heat sink including a phase change material that is capable of absorbing the waste heat generated by the at least one laser diode coupled to the laser mount.

12. The infrared flare of claim 11 wherein a cavity of the heat sink is filled with an open structure impregnated with the phase change material.

13. The infrared flare of claim 12 wherein the open cell structure includes one of an aluminum foam or a graphite foam.

26. The infrared flare of claim 1 wherein the infrared flare weighs less than or equal to 6.95 pounds.

14. An infrared flare comprising:

a cylindrical housing;

a heat sink secured within the cylindrical housing;

an illumination source secured within the cylindrical housing and coupled to an illumination source mount at a first end of the heat sink, the illumination source configured to emit radiation in the near-infrared spectrum; and

an electrical power system secured within the cylindrical housing and coupled to a second end of the heat sink,

wherein the heat sink is configured to absorb waste heat generated by the illumination source and the electrical power system.

15. The infrared flare of claim 14 wherein the heat sink is configured to maintain the illumination source mount at or below 60°

C. during operation of the infrared flare.

16. The infrared flare of claim 14 wherein the heat sink includes a cylindrical body secured within the cylindrical housing, the cylindrical body including at least one cavity filled with a phase change material.

17. The infrared flare of claim 16 wherein the at least one cavity is filled with an open cell structure impregnated with the phase change material, wherein the open cell structure is configured to increase the heat transfer rate into the phase change material.

18. The infrared flare of claim 17 wherein the open cell structure includes one of an aluminum foam or a graphite foam.

19. The infrared flare of claim 14 further comprising at least one light shaping diffuser configured to transform an astigmatic output of the illumination source into a flat top illumination profile or a Gaussian profile.

20. The infrared flare of claim 19 wherein the at least one light shaping diffuser is further configured to remove laser speckle from the output of the illumination source.

21. The flare of claim 14 wherein the illumination source includes a plurality of laser diodes that are configured to emit radiation having a wavelength ranging between 800 nm to 950 nm.

22. The infrared flare of claim 14 wherein the infrared flare is configured to provide an illumination altitude of about 400 meters to about 1000 meters.

23. The infrared flare of claim 14 wherein the infrared flare is configured to provide an illumination area of at least 1500 meters in diameter.

24. The infrared flare of claim 14 wherein the infrared flare has an electrical to optical efficiency of at least 50% at a temperature up to 60°

Celsius.

25. The infrared flare of claim 14 wherein the infrared flare has a flare life of at least 180 seconds.

27. An infrared flare comprising:

means for emitting radiation in the near-infrared spectrum;

means for transforming the radiation output from the means for emitting; and

means for absorbing waste heat generated by the means for emitting,

means for coupling the means for emitting to the means for absorbing, wherein the means for absorbing waste heat is configured to maintain the means for coupling at or below 60°

C. during operation of the infrared flare.

28. An infrared flare system comprising:

an illumination subsystem including at least one diode laser source configured to provide radiation in the near-infrared spectrum;

an optical subsystem configured to remove astigmatism and laser speckle from an output of the at least one diode laser and to transform the output of the at least one laser diode into a Gaussian profile or a flat-top profile, the optical subsystem further configured to provide uniform illumination;

an electronic power control system including a thermal battery configured to supply an operating current to the illumination subsystem; and

a thermal management subsystem including a heat sink and a phase change material, wherein the heat sink and the phase change material are configured to absorb waste heat generated by the flare.

29. The infrared flare system of claim 28 wherein the optical system comprises at least one concentrating parabolic reflector and at least one light shaping diffuser.

30. A method of providing uniform illumination using a flare, comprising:

receiving an output in the near-infrared spectrum from at least one diode laser;

removing laser speckle from the output of the at least one diode laser; and

transforming the output from the at least one diode laser into a Gaussian profile or a flat top profile.

31. The method of claim 30 further comprising delivering the Gaussian profile or the flat top profile to uniformly illuminate a field of view of night vision goggles.

32. The method of claim 30 wherein the at least one laser diode includes a plurality of laser diodes.

33. The method of claim 32 further comprising combining the output from the plurality of laser diodes.